The present invention relates to a heat pump system having a heat exchange circuit wherein a water supply circuit is connected to the cold side thereof with the water in the supply circuit being capable of being supercooled to temperatures below 0.degree. C.
A heat pump is a machine capable of extracting energy from a source at a certain temperature and transferring it to a sink at a higher temperature. It thus can be said that the machine has a "cold side" and a "hot side".
Different types of heat pumps exist: absorption heat pumps, chemical heat pumps, thermoelectrical heat pumps, vapor compression heat pumps, etc. All of these machines need a heat source from which energy can be extracted. That source can be any medium: air, water, ground, etc. The heat sink of the machine can also be any medium.
If the purpose for using the heat pump is to cool a medium, the machine is usually called a refrigeration or a conditioning system. If instead, heating a medium is desired, the machine is simply called a heat pump. It can be noted that the same machine can also have two functions, like cooling the air in a house (cold side) while at the same time heating a swimming pool (hot side), while the heat extracted from the house.
In the particular case where the heat source for the machine is water, the reason for using the heat pump can be to obtain cold water for conditioning purposes; it can also be to fabricate ice which has a large number of uses. Since that phase change (liquid to solid) liberates a large quantity of energy (335 kJ/kg), it can also be regarded as a very large source of heat for the cold side of the heat pump; the heat which is then produced on the hot side can then be used for different purposes, like space heating. A heat pump capable of fabricating ice is usually called an Ice Maker Heat Pump (IMHP).